Computer data in desk-top personal computers (PCs) is ordinarily stored on one of two generic types of direct access memory media, i.e., memory media which can be accessed when the user is on-line with the PC, and these two types of direct access memory media are broadly know as "disks" and "drives". The first type of direct access memory media is familiarly referred to as a "hard disk drive". A hard disk drive may be internal, i.e., it may be mounted within the PC, or external, i.e., it may be located next to the PC, but in either case, hard disk drives require electrical connections to the PC that can be cumbersome and time-consuming to make.
In contrast, a unit of the second type of direct access memory media, familiarly referred to as a "floppy disk", is manually inserted into a portion of the computer familiarly referred to as a floppy disk drive, and a floppy disk can be easily and quickly ejected from the floppy disk drive after data transfer. Thus, a floppy disk can be ejected, i.e., manually urged outwardly from a PC by pushing a button, without requiring that "hard" electrical contacts be unmade. On the other hand, a hard disk drive currently cannot be ejected from a desk-top PC, but must be disconnected from electrical connections in the PC and then removed. Hard disk drives, however, can store much more data than can floppy disks.
Modern PCs typically permit the use of both kinds of memory media, to afford the user of the PC the advantages associated with each. More specifically, as stated above, hard disk drives, which are ordinarily intended to be permanently connected to their respective PCs, have a large data storage capacity. In contrast, floppy disks have much lower data storage capability as compared to hard disk drives, but can easily be ejected from the computer when it is necessary to store data, e.g., confidential military or economic data, apart from the computer, or to transport the data computer-to-computer when a network is not available.
While this arrangement of data storage is useful, it has certain drawbacks. For example, when sensitive military or economic data is to be transferred from the permanent hard disk drive of a PC to a floppy disk for secure storage of the data, the only thing ordinarily "deleted" from the PC hard disk drive after data transfer is the name of the file that contains the data. The data, however, while inaccessible using most software, remains on the hard disk drive, and can be retrieved using specialized software. Thus, once confidential data has been stored on a permanently mounted hard disk drive, both the hard disk drive and it's associated PC must be treated as classified equipage. Understandably, this increases security costs and limits the access of non-cleared users to the PC.
Further, because of their relatively limited data storage capability, floppy disks cannot be used to store large amounts of data. Thus, if a large amount of data is to be transferred from the hard disk drive of a computer, more than a single floppy disk may be required. This increases expenses, tends to be labor-intensive, and requires excessive storage space.
Consequently, when large amounts of data are to be physically moved from a non-secure location to a comparatively secure area for data analysis, the data is ordinarily stored on a hard disk drive which is subsequently disconnected from the so-called host computer and then transported to the secure area. For example, surveillance aircraft tend to collect a large amount of data, and the collected data is stored in relatively bulky hard disk drives that have large data storage capacities. After mission completion, the disk drives are electrically disconnected from their host computers, which as stated above can be cumbersome and time consuming, and then removed from the craft after the mission for data analysis. Furthermore, many large hard disk drives unfortunately are heavy. This is a disadvantage in most computer applications and particularly in applications requiring airborne computer operation, wherein it is generally crucial to minimize the weight and volume of articles that are to be carried onboard the aircraft.
The above discussion focussed on but one application wherein data portability is desirable, but the need for data portability is acute in a wide variety of other applications requiring data transfer between computers. Indeed, regardless of the particular application, a growing need exists to transfer large amounts of data between pairs of the ubiquitous desk-top personal computer. For example, a person who is located at a site remote from his desk-top PC (and its associated hard disk drive on which the person's files and software are stored) may require access to some or all of the data base (i.e., files and software) that is stored on the hard disk drive. When networks or network software are unavailable, the person must take his data base with him. He can do this by disconnecting his hard disk drive from his PC, transporting his hard disk drive with him, and then reconnecting the disk drive to a computer located at the remote site. Alternatively, the person can up-load his data base to a large number of floppy disks one at a time, transport the floppy disks to the remote site, and then down-load the data base from the floppy disks one at a time onto a computer located at the remote site. Unfortunately, both procedures are cumbersome and time-consuming.
In light of the above discussion, the above-referenced parent and grandparent applications, as well as the present invention, recognize a need to provide the portability advantages inherent in floppy disks, without sacrificing the data storage capacity of hard disk drives.
As further recognized by the present invention, owing to the delicate nature of certain components of hard disk drives, particular considerations arise in connection with a portable hard disk drive system wherein the hard disk drive can be easily advanced into and ejected from a PC. For example, certain internal components of hard disk drives rotate very rapidly, and these components must be allowed to "spin down" prior to ejecting the disk drive from the computer. Otherwise, the disk drive could be irreparably damaged. Furthermore, to increase the operational convenience of the PC, provisions should ideally be made for configuring the portable, ejectable hard disk drive as the main drive (i.e., the so-called "C" drive) of the associated PC.
Accordingly, it is an object of the present invention to provide an apparatus that can be associated with a desk-top personal computer and which can hold a portable hard computer disk drive in operable engagement with the computer. Another object of the present invention is to provide an apparatus for easily inserting and ejecting a portable hard disk drive into a desk-top personal computer. Yet another object of the present invention is to provide a portable hard disk drive housing for a desk-top personal computer which is easy to use and cost-effective to manufacture. Still another object of the present invention is to provide a system with a portable, ejectable hard disk drive which automatically permits the disk drive to adequately spin down prior to ejection from an associated PC, and which provides for convenient operation of the PC.